Find intervals on the fretboard fast: 3x3 Box Technique


"They thought they were identifying a set of behaviours, but yeah, they just wanted to have an answer." - Chester Brown

Intervals are more important than the notes themselves.

The way we can build chords and create melodies is by superimposing notes with specific intervals that carry weight or emotion.

In order to be able to come up with those on the fly, especially while improvising, you need to be able to identify the intervals on the fretboard. The faster, the better, of course.

In this lesson, I'll show you my method for finding out the intervals quickly on the fretboard.

Don't forget to check the infographic at the bottom!

If you don't want to read, you can watch the video lesson.

Unless you are using a very unorthodox tuning on your guitar, most of the intervals are placed very closely together on the fretboard. From now on, I'll assume a standard EADGBE tuning, although this will also work for any drop tuning too.

Take a look at this figure:

See the area that's enclosed in the rounded rectangle? It's a 3-fret by 3-string square.

We'll find that most intervals are within that figure. This is why I call this technique the "3x3 Box Technique".

Let's pick any note on the 6th string as a starting note, let's say the 5th fret, which corresponds to an A note. The most important and straightforward intervals are the 5th (E) and the 8th (octave, A), which can be found within the figure:

Of course, the numbers in this case mean the intervals, not fingers!

These notes tend are usually the strongest notes you can play on top of most chords, since they are the notes that appear in almost all chords. Playing them will always sound right.

In my opinion, these notes are the easiest to find starting from the root.

There are more intervals to be found there as well: 2nd (B), 4th (D), and 7th (Ab).

By focusing on this single block figure, it's much easier to identify the intervals all over the fretboard, starting from a root note.

There are two more intervals which are very important that we cannot find in this figure technically. These are the major and minor 3rd (C# and C respectively), which lie just outside the figure.

These are the only two extra intervals you'll have to refer to.

This are the complete intervals:

The interesting thing about this pattern is that it can be moved anywhere on the fretboard, with the root notes in any string. You can even use it backwards, that is consider the octave note as the root note and find the same intervals.

Here's how it looks on a root note on the 5th string: